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Find video protocols related to scientific articles indexed in Pubmed.
Wavelength-locking-free 1.57µm differential absorption lidar for CO2 sensing.
Opt Express
PUBLISHED: 11-18-2014
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We propose a novel wavelength-locking-free differential absorption lidar system for CO2 sensing. The ON-line wavelength laser was wavelength modulated around a specific CO2 absorption line to ensure that the emission from the ON-line laser hit the atmospheric CO2 absorption line peak twice a cycle. In the meantime, the intensity of the ON-line and OFF-line wavelength lasers were sinusoidally intensity modulated to enhance the SNR of the back-scattered signal. As a consequence, the system configuration was simplified and the measurement error caused by the deviation of CO2 absorption coefficient from the long-time ON-line wavelength drifting was completely eliminated. Furthermore, a more precise calibration method was developed which could simultaneously calibrate the offset and precision of the lidar detector. This method could be applied to other differential-absorption-based lidar systems. The result showed that a measurement precision of 0.525% for the column concentration was achieved in 1 s time interval through a path of 780m. We recorded the CO2 concentration variation for 12 hours starting from mid-night, the result showed that the course of the concentration derived from the DIAL was in good agreement with that of the in situ CO2 sensor only when the status of atmosphere was stable.
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Microfiber-based, highly nonlinear graphene saturable absorber for formation of versatile structural soliton molecules in a fiber laser.
Opt Express
PUBLISHED: 11-18-2014
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We reported on the generation of versatile soliton molecules in a fiber laser mode-locked by a microfiber-based graphene saturable absorber (GSA). By virtue of the highly nonlinear effect of the microfiber-based GSA, the soliton molecules could be easily observed. In addition to regular soliton molecules, it is found that the "soliton atoms" in molecules could exhibit different characteristics and show ultra-narrow pulse separations, which was termed as 'structural soliton molecule'. The pulse profiles of 'structural soliton molecules' were further reconstructed theoretically. The obtained results would give further insight towards understanding the dynamics of soliton molecules in fiber lasers.
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Serial in vivo imaging using a fluorescence probe allows identification of tumor early response to cetuximab immunotherapy.
Mol. Pharm.
PUBLISHED: 11-15-2014
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Cetuximab is an anti-epidermal growth factor receptor monoclonal antibody that has received the approval of the Food and Drug Administration (FDA) for cancer treatment. However, most clinical studies indicate that cetuximab can only elicit positive effects on a subset of cancer patients. In this study, we investigated whether near-infrared fluorescence (NIRF) imaging of tumor vascular endothelial growth factor (VEGF) expression could be a biomarker for tumor early response to cetuximab therapy in preclinical wild-type and mutant tumor models of the KRAS gene. The treatment efficacy of cetuximab was determined in both HT-29 (wild-type KRAS) and HTC-116 (mutant KRAS) human colon cancer models. A VEGF-specific optical imaging probe (Dye755-Ran) was synthesized by conjugating ranibizumab (an anti-VEGF antibody Fab fragment) with a NIRF dye. Serial optical scans with Dye755-Ran were performed in HT-29 and HTC-116 xenograft models. By using longitudinal NIRF imaging, we were able to detect early tumor response on day 3 and day 5 after initiation of cetuximab treatment in the cetuximab-responsive HT-29 tumor model. Enzyme-linked immunosorbent assay (ELISA) confirmed that cetuximab treatment inhibited VEGF expression in the KRAS wild-type HT-29 tumor but not in the KRAS mutant HCT-116 tumor. We have demonstrated that the antitumor effect of cetuximab can be noninvasively monitored by serial fluorescence imaging using Dye755-Ran. VEGF expression detected by optical imaging could serve as a sensitive biomarker for tumor early response to drugs that directly or indirectly act on VEGF.
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Design and Optimization of a Phosphopeptide Anchor for Specific Immobilization of a Capture Protein on Zirconium Phosphonate Modified Supports.
Langmuir
PUBLISHED: 11-04-2014
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The attachment of affinity proteins onto zirconium phosphonate coated glass slides was investigated by fusing a short phosphorylated peptide sequence at one extremity to enable selective bonding to the active surface via the formation of zirconium phosphate coordinate covalent bonds. In a model study, the binding of short peptides containing zero to four phosphorylated serine units and a biotin end-group was assessed by surface plasmon resonance-enhanced ellipsometry (SPREE) as well as in a microarray format using fluorescence detection of AlexaFluor 647-labeled streptavidin. Significant binding to the zirconated surface was only observed in the case of the phosphopeptides, with the best performance, as judged by streptavidin capture, observed for peptides with three or four phosphorylation sites and when spotted at pH 3. When fusing similar phosphopeptide tags to the affinity protein, the presence of four phosphate groups in the tag allows efficient immobilization of the proteins and efficient capture of their target.
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Targeted Delivery of Anticancer Agents via a Dual Function Nanocarrier with an Interfacial Drug-Interactive Motif.
Biomacromolecules
PUBLISHED: 10-28-2014
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We have developed a dual-function drug carrier, polyethylene glycol (PEG)-derivatized farnesylthiosalicylate (FTS). Here we report that incorporation of a drug-interactive motif (Fmoc) into PEG5k-FTS2 led to further improvement in both drug loading capacity and formulation stability. Doxorubicin (DOX) formulated in PEG5k-Fmoc-FTS2 showed sustained release kinetics slower than those of DOX loaded in PEG5k-FTS2. The maximum tolerated dose of DOX- or paclitaxel (PTX)-loaded PEG5k-Fmoc-FTS2 was significantly higher than that of the free drug. Pharmacokinetics and biodistribution studies showed that DOX/PEG5k-Fmoc-FTS2 mixed micelles were able to retain DOX in the bloodstream for a significant amount of time and efficiently deliver the drug to tumor sites. More importantly, drug (DOX or PTX)-loaded PEG5k-Fmoc-FTS2 led to superior antitumor activity over other treatments including drugs formulated in PEG5k-FTS2 in breast cancer and prostate cancer models. Our improved dual function carrier with a built-in drug-interactive motif represents a simple and effective system for targeted delivery of anticancer agents.
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[Effect of (E)-2-(4-bromophenyl )-1-(3,4-dihydroxyphenyl )ethanone oxime on proliferation and activation of mice lymphocytes].
Sichuan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 10-25-2014
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To study the effects of (E)-2-(4-bromophenyl)-1-(3, 4-dihydroxyphenyl) ethanone oxime (BDEO) on the proliferation and activation of the mice' s splenic lymphocytes and the peripheral blood lymphocytes induced by Concanavalin A (Con A) in vitro and in vivo, and its molecular mechanism.
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Microfiber-based few-layer MoS2 saturable absorber for 2.5 GHz passively harmonic mode-locked fiber laser.
Opt Express
PUBLISHED: 10-17-2014
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We reported on the generation of high-order harmonic mode-locking in a fiber laser using a microfiber-based molybdenum disulfide (MoS2) saturable absorber (SA). Taking advantage of both the saturable absorption and large third-order nonlinear susceptibilities of the few-layer MoS2, up to 2.5 GHz repetition rate HML pulse could be obtained at a pump power of 181 mW, corresponding to 369th harmonic of fundamental repetition frequency. The results provide the first demonstration of the simultaneous applications of both highly nonlinear and saturable absorption effects of the MoS2, indicating that the microfiber-based MoS2 photonic device could serve as high-performance SA and highly nonlinear optical component for application fields such as ultrafast nonlinear optics.
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Puerarin Enhances Bone Mass by Promoting Osteoblastogenesis and Slightly Lowering Bone Marrow Adiposity in Ovariectomized Rats.
Biol. Pharm. Bull.
PUBLISHED: 10-10-2014
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We investigated the effect of puerarin on bone mass and marrow adiposity in ovariectomy (OVX)-induced osteoporosis. The rats were divided into four groups: control; OVX; OVX + estradiol (OVX-E); and OVX + puerarin treatment (OVX-GE). In vivo, Bone mineral density (BMD) and histomorphometry were measured under microCT. The mechanical properties of tibia were obtained in 3-point bending test. Plasma osteocalcin and adiponectin were determined using ELISA. Alkaline phosphatase (ALP) were measured using biochemical methods. In vitro, MTT and Oil Red O staining were used to compare osteoblast proliferation and adipocyte differentiation, respectively. Osteocalcin and adiponectin in culture supernatants were determined using ELISA. The results showed that puerarin significantly enhanced bone volume density and trabecular number compared with OVX and OVX-E groups (P < 0.05, P < 0.05, respectively). Puerarin increased energy to ultimate load, plasma osteocalcin and ALP (P < 0.01). However, BMD in OVX-GE group was less than that in control (P < 0.01) and OVX-E groups (P < 0.05). The culture supernatants from OVX-GE group showed increased osteocalcin compared with those from OVX (P < 0.01) and OVX-E groups (P < 0.05). Puerarin lowered adiponectin in culture supernatant compared with supernatant from OVX group and inhibited the increase in adipocytes caused by OVX (P < 0.01). However, the amount of lipids did not differ between OVX-GE and OVX groups. These findings suggest that puerarin likely enhances bone formation by stimulating the proliferation and differentiation of osteoblasts while slightly inhibiting the adipotic differentiation.
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[Effects and mechanisms of punicosides on acute alcoholic liver damage in mice].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-03-2014
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To evaluate the protective effects of punicosides on alcohol induced acute liver injury in mice and its possible mechanisms as well.
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The Effect of Deviated Center of Rotation on Flexion-Extension Range of Motion after Single-Level Cervical Arthroplasty: An in Vivo Study.
Spine
PUBLISHED: 10-02-2014
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Study Design. A retrospective study.Objective. To report the clinical outcomes and sagittal kinematics following cervical total disc replacement (TDR). To evaluate the in vivo effect of deviated center of rotation (COR) on flexion/extension range of motion (ROM) at the instrumented level.Summary of Background Data. A few studies showed that the location of COR after cervical TDR deviated from its preoperative location or inherent location in healthy subjects. However, little is known about the effect of deviated COR on ROM at the instrumented level.Methods. A total of 24 patients who underwent C5-C6 single-level TDR with Prestige LP (Medtronic Sofamor Danek, Memphis, TN) were retrospectively included. Japanese Orthopedic Association (JOA) score and visual analogue scale (VAS) were used to assess the clinical outcomes. ROM and COR were measured for radiographic analysis. Patients were categorized into 2 groups according to the change of ROM for further evaluation. Group 1, characterized by decreased postoperative ROM, consisted of 16 patients; group 2, characterized by increased postoperative ROM, consisted of 8 patients.Results. There were 10 males and 14 females. The mean age was 45.05 years, and the mean follow-up time was 15.5 months. The JOA score increased significantly and the neck and arm VAS decreased significantly after cervical TDR. On average, ROM was preserved after cervical TDR. The postoperative COR had a significant cranial shift from its preoperative location. The COR shift in anterior-posterior direction was larger in group 2 than that in group 1. No difference was observed in the COR shift in cranial-caudal direction between the 2 groups.Conclusion. Single-level cervical TDR with Prestige LP obtained satisfactory clinical outcomes and partially restored the natural cervical kinematics. At instrumented level, the deviated COR had a negative correlation with the flexion/extension ROM.
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Targeted delivery of Doxorubicin by folic Acid-decorated dual functional nanocarrier.
Mol. Pharm.
PUBLISHED: 09-29-2014
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Doxorubicin (DOX) is one of the most commonly used antineoplastic agents, but its clinical application is oftentimes coupled with severe side effects. Selective delivery of DOX to tumors via nanosized drug carrier represents an attractive approach to this problem. Previously, we developed a dual functional nanomicellar carrier, PEG5K-embelin2 (PEG5K-EB2), which was able to deliver paclitaxel (PTX) selectively to tumors and to achieve an enhanced therapeutic effect. In the present study, we examined the utility of PEG5K-EB2 to deliver DOX to tumors. In addition, folic acid (FA) was coupled to the surface of the PEG5K-EB2 micelles (FA-PEG5K-EB2) to further improve the selective targetability of the system. DOX-loaded PEG5K-EB2 micelles were uniformly spherical particles with a diameter of approximately 20 nm. Incorporation of FA had minimal effect on the size of the particles. The DOX loading efficiency was as high as 91.7% and 93.5% for PEG5K-EB2 and FA-PEG5K-EB2, respectively. DOX formulated in PEG5K-EB2 micelles (with or without FA decoration) demonstrated sustained kinetics of DOX release compared to free DOX. FA-PEG5K-EB2 significantly facilitated the intracellular uptake of DOX over free DOX and PEGylated liposomal DOX (Doxil) in breast cancer cells, 4T1.2, and drug resistant cells, NCI/ADR-RES. P-gp ATPase assay showed that PEG5K-EB2 significantly inhibited the function of the P-gp efflux pump. The maximum tolerated dose of DOX-loaded PEG5K-EB2 micelles was 15 mg/kg in mice, which was 1.5-fold greater than that for free DOX. Pharmacokinetics (PK) and biodistribution studies showed that both types of DOX-loaded micelles, especially FA-PEG5K-EB2, were able to significantly prolong the blood circulation time of DOX and facilitate its preferential accumulation at the tumor tissue. Finally, DOX/PEG5K-EB2 mixed micelles demonstrated significantly enhanced tumor growth inhibitory effect with minimal toxicity in comparison to free DOX and Doxil and the antitumor activity was further enhanced after the decoration by folic acid. Our data suggest that FA-PEG5K-EB2 micelles represent a promising DOX delivery system that warrants more study in the future.
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Feasibility of conventional and single-stage anaerobic ammonium oxidation processes for treating chlortetracycline wastewater.
Water Sci. Technol.
PUBLISHED: 09-27-2014
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Conventional and single-stage anaerobic ammonium oxidation (ANAMMOX) was carried out in bench-scale reactors to treat chlortetracycline (CTC) wastewater. The total nitrogen (TN) removal efficiency and rate for conventional ANAMMOX was 66.6 ± 5.9% and 2.7 ± 0.2 kg N/(m³·d), respectively, which was 58.6 ± 3.8% and 1.2 ± 0.1 kg N/(m³·d) for single-stage ANAMMOX. Single-stage ANAMMOX showed higher tolerance to CTC than conventional ANAMMOX. The nitrogen removal of conventional and single-stage ANAMMOX began to deteriorate when CTC was added, to 40 and 80 mg/L, respectively, with the former totally inhibited at 120 mg/L CTC and the latter at 140 mg/L CTC. TN removal rates were recovered to 1.2 and 0.7 kg N/(m³·d), respectively, when CTC concentration was reduced to 20 mg/L for 8 days. This study implied that ANAMMOX could be efficiently used to treat pharmaceutical wastewater, with single-stage implementation being more stable under antibiotic pressure.
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Stratification analysis and case-control study of relationships between interleukin-6 gene polymorphisms and cervical cancer risk in a Chinese population.
Asian Pac. J. Cancer Prev.
PUBLISHED: 09-18-2014
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Interleukin-6 (IL-6), a central proinflammatory cytokine, maintains immune homeostasis and also plays important roles in cervical cancer. Therefore, we aimed to evaluate any associations of IL-6 gene polymorphisms at positions -174 and -572 with predisposition to cervical cancer in a Chinese population. The present hospital- based case-control study comprised 518 patients with cervical cancer and 518 healthy controls. Polymorphisms of the IL-6 gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Patients with cervical cancer had a significantly higher frequency of the IL-6 -174 CC genotype [odds ratio (OR) =1.52, 95% confidence interval (CI) = 1.06-2.19; p=0.02], IL-6 -572 CC genotype (OR =1.91, 95% CI = 1.16-3.13; p=0.01) and IL-6 -174 C allele (OR =1.21, 95% CI = 1.02-1.44; p=0.03) compared to healthy controls. When stratifying by the FIGO stage, patients with III-IV cervical cancer had a significantly higher frequency of IL-6 -174 CC genotype (OR =1.64, 95% CI =1.04-2.61; p=0.04). The CC genotypes of the IL-6 gene polymorphisms at positions -174 and -572 may confer a high risk of cervical cancer. Additional studies with detailed human papillomavirus (HPV) infection data are warranted to validate our findings.
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Improve accuracy for automatic acetabulum segmentation in CT images.
Biomed Mater Eng
PUBLISHED: 09-18-2014
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Separation of the femur head and acetabulum is one of main difficulties in the diseased hip joint due to deformed shapes and extreme narrowness of the joint space. To improve the segmentation accuracy is the key point of existing automatic or semi-automatic segmentation methods. In this paper, we propose a new method to improve the accuracy of the segmented acetabulum using surface fitting techniques, which essentially consists of three parts: (1) design a surface iterative process to obtain an optimization surface; (2) change the ellipsoid fitting to two-phase quadric surface fitting; (3) bring in a normal matching method and an optimization region method to capture edge points for the fitting quadric surface. Furthermore, this paper cited vivo CT data sets of 40 actual patients (with 79 hip joints). Test results for these clinical cases show that: (1) the average error of the quadric surface fitting method is 2.3 (mm); (2) the accuracy ratio of automatically recognized contours is larger than 89.4%; (3) the error ratio of section contours is less than 10% for acetabulums without severe malformation and less than 30% for acetabulums with severe malformation. Compared with similar methods, the accuracy of our method, which is applied in a software system, is significantly enhanced.
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[Expression of indoleamine 2, 3-dioxygenase modulates macrophage polarization in THP-1 cells].
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi
PUBLISHED: 09-10-2014
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Objective To investigate whether indoleamine 2, 3-dioxygenase (IDO) has an effect on macrophage polarization of differentiated THP-1 (dTHP-1) cells. Methods The macrophage model was established through incubating the human monocyte line (THP-1 cells) with phorbol-12-myristate 13-acetate (PMA) (10 ng/mL) for 48 hours. To generate M1/M2-polarized macrophages, dTHP-1 cells were cultured with IFN-? (100 U/mL) and M-CSF (100 ng/mL), respectively. The expressions of molecular markers of macrophages (including HLA-DR, CCR7, IL-12p35, IL-10, CXCR4) and IDO were examined by real-time quantitative PCR (qRT-PCR), flow cytometry, and Western blotting. To investigate the role of IDO in the dTHP-1 cell polarization, the plasmid pEGFP-N1-IDO and siRNA-IDO were respectively transfected into cells. The mRNA levels of molecular markers of macrophages were examined by qRT-PCR. Results IFN-? could induce the differentiation of THP-1 cells into M1 phenotype and up-regulate the IDO expression. Interestingly, our results also indicated that the ectopic IDO could trigger the transformation of dTHP-1 cells to M2 phenotype. In contrast, the knockdown of IDO expression in dTHP-1 cells resulted in increased M1 markers and lower M2 markers. Conclusion The expression intensity of IDO could modulate macrophage polarization in THP-1 cells.
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A new dimeric neolignan from Magnolia grandiflora L. seeds.
Arch. Pharm. Res.
PUBLISHED: 09-06-2014
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Bioassay-guided fractionation of the MeOH extract of Magnolia grandiflora seeds resulted in the isolation of a new dimeric neolignan, named bishonokiol A (1), as well as two known neolignans magnolol (2) and honokiol (3). The structures of the compounds were determined on the basis of data obtained using NMR and MS. Bishonokiol A (1) showed potent anti-proliferative activities in four human cancer cell lines, with IC50 values ranging from 5.1 to 7.5 µM. Additionally, bishonokiol A (1) induced apoptosis, as well as down-regulated the expression of the anti-apoptotic protein Bcl-2 and caspase-3 cleavage in HepG2 cell line.
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Transcriptome differences in the hypopharyngeal gland between Western Honeybees (Apis mellifera) and Eastern Honeybees (Apis cerana).
BMC Genomics
PUBLISHED: 08-30-2014
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Apis mellifera and Apis cerana are two sibling species of Apidae. Apis cerana is adept at collecting sporadic nectar in mountain and forest region and exhibits stiffer hardiness and acarid resistance as a result of natural selection, whereas Apis mellifera has the advantage of producing royal jelly. To identify differentially expressed genes (DEGs) that affect the development of hypopharyngeal gland (HG) and/or the secretion of royal jelly between these two honeybee species, we performed a digital gene expression (DGE) analysis of the HGs of these two species at three developmental stages (newly emerged worker, nurse and forager).
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Ischemic injury of the liver in a porcine model of cardiac death assessed by in vivo microdialysis.
Mol. Biol. Rep.
PUBLISHED: 08-29-2014
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This study aims to evaluate the ischemic injury of the liver in a porcine model of cardiac death assessed by in vivo microdialysis. A porcine model of cardiac death was established by the suffocation method. Metabolic indicators were monitored using the microdialysis technique during warm ischemia time (WIT) and cold ischemia time (CIT). Pathological changes in ischemic-injured livers were observed by haematoxylin-eosin staining. The predictive values of biochemical parameters regarding the liver donor were evaluated by receiver operating characteristic curve analysis. All statistical analyses were conducted using the SPSS 18.0 software (SPSS Inc, Chicago, Illinois, USA). The degree of warm ischemic injury of the livers increased with prolonged WIT. Serum glucose, glycerol, pyruvate, lactic acid levels and lactate-to-pyruvate (L/P) ratio increased gradually during WIT. Results from Pearson correlation analyses indicated that serum lactate level and L/P ratio were positively associated with the degree of warm ischemic injury of the livers. The degree of cold ischemic injury of the livers gradually increased after 12 h CIT. Serum glucose, lactic acid and L/P ratio achieved a peak after 6-8 h of CIT, but gradually decreased with prolonged CIT. The peak of glycerol occurred after 8 h of CIT, while no changes were found with prolonged CIT. Serum pyruvate level exhibited an increasing trend after 12 h CIT. Our results confirmed that serum glucose and lactate levels were negatively correlated with cold ischemic injury of the liver. However, serum glycerol and pyruvate levels showed positive correlations with cold ischemic injury of the liver. The liver donor was unavailable after 30 min WIT and 24 h CIT. The cut-off value of serum lactate level for warm ischemic injury of the livers was 2.374 with a sensitivity (Sen) of 90 % and specificity (Spe) of 95 %; while the L/P radio was 0.026 (Sen = 80 %, Spe = 83 %). In addition, the cut-off values of serum glucose, lactate, glycerol and pyruvate levels for cold ischemic injury of the livers were 0.339 (Sen = 100 %, Spe = 77 %), 1.172 (Sen = 100 %, Spe = 61 %), 56.359 (Sen = 100 %, Spe = 65 %) and 0.020 (Sen = 100 %, Spe = 67 %), respectively. Our findings provide empirical evidences that serum glucose, lactate levels and L/P ratio may be good indicators for the degree of warm ischemic injury of the livers after cardiac death; while serum glucose, lactate, glycerol and pyruvate levels may be important in predicting cold ischemic injury.
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RoGFP1 is a quantitative biosensor in maize cells for cellular redox changes caused by environmental and endogenous stimuli.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-27-2014
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Reduction-oxidation-sensitive green fluorescent proteins (roGFPs) have been demonstrated to be valuable tools in sensing cellular redox changes in mammalian cells and model plants, yet have not been applied in crops such as maize. Here we report the characteristics of roGFP1 in transiently transformed maize mesophyll protoplasts in response to environmental stimuli and knocked-down expression of ROS-scavenging genes. We demonstrated that roGFP1 in maize cells ratiometrically responds to cellular redox changes caused by H2O2 and DTT, as it does in mammalian cells and model plants. Moreover, we found that roGFP1 is sensitive enough to cellular redox changes caused by genetic perturbation of single ROS genes, as exemplified by knocked-down expression of individual ZmAPXs, in maize protoplasts under controlled culture conditions and under stress conditions imposed by H2O2 addition. These data provide evidence that roGFP1 functions in maize cells as a biosensor for cellular redox changes triggered by genetic lesion of single ROS genes even under stress conditions, and suggest a potential application of roGFP1 in large-scale screening for maize mutants of ROS signaling involved in development and stress resistance.
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SET-mediated NDRG1 inhibition is involved in acquisition of epithelial-to-mesenchymal transition phenotype and cisplatin resistance in human lung cancer cell.
Cell. Signal.
PUBLISHED: 08-23-2014
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Development of resistance to therapy continues to be a serious clinical problem in lung cancer management. Cancer cells undergoing epithelial-to-mesenchymal transition (EMT) have been shown to play roles in resistance to chemotherapy. Here, we utilized a proteomics-based method and identified a significant downregulation of the metastasis suppressor NDRG1 in drug resistant lung cancer cells. We showed that downregulation of DNRG1 constitutes a mechanism for acquisition of EMT phenotype and endows lung cancer cells with an increased resistance to cisplatin. We also identified a signal cascade, namely, SET---| PP2A---| c-myc---| NDRG1, in which upregulation of SET is critical for inhibition of NDRG1. We also found that blockade of SET (or reactivation of PP2A) by FTY720 reverted EMT, restored drug sensitivity, and inhibited invasiveness and growth of lung tumor xenografts. Together, our results indicated a functional link between SET-mediated NDRG1 regulation and acquisition of EMT phenotype and drug resistance, and provided an evidence that blockade of SET-driven EMT can overcome drug resistance and inhibit tumor progression.
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Genetic and Functional Characterization of the Hyaluronate Lyase HylB and the Beta-N-Acetylglucosaminidase HylZ in Streptococcus zooepidemicus.
Curr. Microbiol.
PUBLISHED: 08-22-2014
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Hyaluronic acid (hyaluronan) is a high molecular weight glycosaminoglycan composed of repeating disaccharides of glucuronic acid and N-acetylglucosamine. The molecular weight of hyaluronan is important for its rheological property, biological function, and application. However, genes important for regulation of hyaluronan production or molecular weight remain poorly understood. Here, we address the roles of two predicated hyaluronate lyase-encoding genes, hylB and hylZ in Streptococcus zooepidemicus. Semi-quantitative RT-PCR assays showed that hylZ was constitutively expressed while the expression level of hylB was growth-phase dependent. Using recombinantly expressed 6His-HylB and -HylZ protein, enzyme assays revealed that HylB was a hyaluronate lyase, and its K m and V max were 0.57 ?M and 1.43 mM min(-1), respectively. 6His-HylZ showed no activity against hyaluronan while it hydrolyzed pNp-?-GlcNAc suggesting that HylZ was a beta-N-acetylglucosaminidase. Under the optimal conditions (pH 6.0 and 50 °C), the K m and V max for 6His-HylZ to degrade pNp-?-GlcNA were 1.16 mM and 26.18 ?mol min(-1) mg(-1), respectively. Characterization of ?hylB and ?hylZ demonstrated that loss of hylB or/and hylZ had no significant effects on cell growth, lactic acid, and hyaluronan yields. Significantly, as compared to the wild type, ?hylB produced hyaluronan with an 18 % increase in molecular weight. Our results strongly suggest that hylB encodes a hyaluronate lyase while hylZ encodes a ?-N-acetylglucosaminidase. hylB-deficient strain has the potential to produce high molecular weight hyaluronan.
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Factors influencing apical node metastasis in colorectal cancer patients treated with laparoscopic radical resection with D3 lymphadenectomy: results from two centers in China.
Surg. Today
PUBLISHED: 08-22-2014
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To identify the risk factors for apical node metastasis in colorectal cancer (CRC) patients who underwent laparoscopic radical resection with D3 lymphadenectomy.
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Uncovering the information core in recommender systems.
Sci Rep
PUBLISHED: 08-21-2014
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With the rapid growth of the Internet and overwhelming amount of information that people are confronted with, recommender systems have been developed to effectively support users' decision-making process in online systems. So far, much attention has been paid to designing new recommendation algorithms and improving existent ones. However, few works considered the different contributions from different users to the performance of a recommender system. Such studies can help us improve the recommendation efficiency by excluding irrelevant users. In this paper, we argue that in each online system there exists a group of core users who carry most of the information for recommendation. With them, the recommender systems can already generate satisfactory recommendation. Our core user extraction method enables the recommender systems to achieve 90% of the accuracy of the top-L recommendation by taking only 20% of the users into account. A detailed investigation reveals that these core users are not necessarily the large-degree users. Moreover, they tend to select high quality objects and their selections are well diversified.
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Efficacy and safety of novel epicardial circumferential left atrial ablation with pulmonary vein isolation in sustained atrial fibrillation.
Heart Vessels
PUBLISHED: 08-19-2014
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The aim of this study was to examine the efficacy and safety of this novel epicardial circumferential left atrial ablation (CLAA) with pulmonary vein isolation (PVI) in sustained atrial fibrillation (AF). Thirty domestic pigs were divided equally into 3 groups: AF without ablation (AF group), AF with PVI (PVI group), and AF with CLAA and PVI (CLAA + PVI group). AF was induced by rapid atrial pacing. After AF was induced, CLAA and PVI were performed for pigs in CLAA + PVI group, and PVI was performed for pigs in PVI group. AF vulnerability, AF duration, and histology were performed in all groups. All pigs developed sustained AF after 6.27 ± 0.69 weeks of rapid atrial pacing. All pigs successfully underwent isolated PVI or CLAA with PVI on the beating heart in PVI group or CLAA + PVI group. Isolated PVI terminated AF in 3 of 20 pigs (15 %), and CLAA with PVI terminated AF in 5 of 8 pigs (62.5 %, P = 0.022). Compared with AF group (10/10), the incidence of sustained AF by burst pacing was significantly decreased in PVI group (3/10, P = 0.003) or CLAA + PVI group (0/10, P < 0.001). There was no significant difference between PVI group and CLAA + PVI group (P = 0.211). AF duration was significantly decreased in CLAA + PVI group (734.70 ± 177.81 s, 95 % CI 607.51-861.89) compared with PVI group (1217.90 ± 444.10 s, 95 % CI 900.21-1535.59, P = 0.008). Also, AF duration was significantly decreased in PVI group (P = 0.003) or CLAA + PVI group (P < 0.001) in comparison with AF duration in AF group (average 1800 s). Epicardial CLAA could ablate the left atrial roof and posterior wall together safely and reliably. Compared with PVI alone, CLAA with PVI may be able to improve the rate of acute termination of persistent AF. It may be useful in selecting the best ablation approaches for patients with persistent AF.
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Drug loaded homogeneous electrospun PCL/gelatin hybrid nanofiber structures for anti-infective tissue regeneration membranes.
Biomaterials
PUBLISHED: 08-16-2014
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Infection is the major reason for guided tissue regeneration/guided bone regeneration (GTR/GBR) membrane failure in clinical application. In this work, we developed GTR/GBR membranes with localized drug delivery function to prevent infection by electrospinning of poly(?-caprolactone) (PCL) and gelatin blended with metronidazole (MNA). Acetic acid (HAc) was introduced to improve the miscibility of PCL and gelatin to fabricate homogeneous hybrid nanofiber membranes. The effects of the addition of HAc and the MNA content (0, 1, 5, 10, 20, 30, and 40 wt.% of polymer) on the properties of the membranes were investigated. The membranes showed good mechanical properties, appropriate biodegradation rate and barrier function. The controlled and sustained release of MNA from the membranes significantly prevented the colonization of anaerobic bacteria. Cells could adhere to and proliferate on the membranes without cytotoxicity until the MNA content reached 30%. Subcutaneous implantation in rabbits for 8 months demonstrated that MNA-loaded membranes evoked a less severe inflammatory response depending on the dose of MNA than bare membranes. The biodegradation time of the membranes was appropriate for tissue regeneration. These results indicated the potential for using MNA-loaded PCL/gelatin electrospun membranes as anti-infective GTR/GBR membranes to optimize clinical application of GTR/GBR strategies.
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Snail regulated by PKC/GSK-3? pathway is crucial for EGF-induced epithelial-mesenchymal transition (EMT) of cancer cells.
Cell Tissue Res.
PUBLISHED: 08-16-2014
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Cancer metastasis is considered a major challenge in cancer therapy. Recently, epidermal growth factor (EGF)/epidermal growth factor receptor (EGFR) signaling has been shown to induce epithelial-mesenchymal transition (EMT) and thereby to promote cancer metastasis. However, the underlying mechanism has not been fully elucidated. We demonstrate that EGF can induce EMT in human prostate and lung cancer cells and thus promote invasion and migration. EGF-induced EMT has been characterized by the cells acquiring mesenchymal spindle-like morphology and increasing their expression of N-cadherin and fibronectin, with a concomitant decrease of E-cadherin. Both protein and mRNA expression of transcription factor Snail rapidly increases after EGF treatment. The knockdown of Snail significantly attenuates EGF-induced EMT, suggesting that Snail is crucial for this process. To determine the way that Snail is accumulated, we demonstrate (1) that EGF promotes the stability of Snail via inhibiting the activity of glycogen synthase kinase 3 beta (GSK-3?), (2) that protein kinase C (PKC) rather than the phosphatidylinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway is responsible for GSK-3? inhibition and (3) that GSK-3? inhibition promotes the transcription of Snail. Taken together, these results reveal that the PKC/GSK-3? signaling pathway controls both the stability and transcription of Snail, which is crucial for EMT induced by EGF in PC-3 and A549 cells. Our study suggests a novel signaling pathway for Snail regulation and provides a better understanding of growth-factor-induced tumor EMT and metastasis.
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Preventive effect of Actinidia valvata Dunn extract on N-methyl-N'-nitro-N-nitrosoguanidine-induced gastrointestinal cancer in rats.
Asian Pac. J. Cancer Prev.
PUBLISHED: 08-16-2014
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This study was conducted to assess the preventive effect of Actinidia valvata Dunn (AVD) extract on an animal model of gastrointestinal carcinogenesis on the basis of changes in tumor incidence, cell proliferation, and apoptosis.
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Bisphenol A modulates colorectal cancer protein profile and promotes the metastasis via induction of epithelial to mesenchymal transitions.
Arch. Toxicol.
PUBLISHED: 08-15-2014
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More and more evidences indicate that endocrine disruptor chemicals such as bisphenol A (BPA) can act as carcinogens and enhance susceptibility to tumorigenesis. Although the gut is in direct contact with orally ingested BPA, effects of BPA on occurrence and development of colorectal cancer remain an unexplored endpoint. Colorectal cancer SW480 cells treated with nanomolar (10(-8) M) or greater (10(-5) M) concentrations of BPA were compared with responses of a control group. Proteomic study revealed that more than 56 proteins were modulated following exposure to BPA, which are relevant to structure, motility and proliferation of cells, production of ATP, oxidative stress, and protein metabolism. Further studies revealed that BPA increased migration and invasion and triggered transformations from epithelial to mesenchymal transitions (EMTs) of colorectal cancer cells, which was characterized by acquiring mesenchymal spindle-like morphology and increasing the expression of N-cadherin with a concomitant decrease of E-cadherin. Accordingly, BPA treatment increased the expression of transcription factor Snail. Furthermore, signal AKT/GSK-3?-mediated stabilization of Snail is involved during BPA-induced EMT of colon cancer cells. Our study first demonstrated that the xenoestrogen BPA at nanomolar and greater concentrations modulates the protein profiles and promotes the metastasis of colorectal cancer cells via induction of EMT.
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Modulation of cytokine expression in human macrophages by endocrine-disrupting chemical Bisphenol-A.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-13-2014
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Exposure to environmental endocrine-disrupting chemical Bisphenol-A (BPA) is often associated with dysregulated immune homeostasis, but the mechanisms remain unclear. In the present study, the effects of BPA on the cytokines responses of human macrophages were investigated. Treatment with BPA increased pro-inflammation cytokines tumor necrosis factor-? (TNF-?) and interleukin-6 (IL-6) production, but decreased anti-inflammation cytokines interleukin-10 (IL-10) and transforming growth factor-? (TGF-?) production in THP1 macrophages, as well as in primary human macrophages. BPA effected cytokines expression through estrogen receptor ?/? (ER?/?)-dependent mechanism with the evidence of ER?/? antagonist reversed the expression of cytokines. We also identified that activation of extracellular regulated protein kinases (ERK)/nuclear factor ?B (NF-?B) signal cascade marked the effects of BPA on cytokines expression. Our results indicated that BPA effected inflammatory responses of macrophages via modulating of cytokines expression, and provided a new insight into the link between exposure to BPA and human health.
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Is Nasogastric or Nasojejunal Decompression Necessary Following Gastrectomy for Gastric Cancer? A Systematic Review and Meta-Analysis of Randomised Controlled Trials.
J. Gastrointest. Surg.
PUBLISHED: 08-09-2014
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Whether nasogastric or nasojejunal decompression (ND) prevents anastomotic leakage, hastens the return of bowel function, and shortens hospital stay after gastrectomy for gastric cancer has long been controversial. We evaluated the necessity of routine ND after radical gastrectomy for gastric cancer with a systematic review and meta-analysis. We searched literature published prior to January 2014 in PubMed, Embase, Cochrane Library, Web of Science, and BIOSIS Previews for relevant randomized controlled trials (RCTs). Only prospective RCTs comparing individuals with and without ND after gastrectomy for gastric cancer were included. Outcome measures included time to first flatus, time to starting oral diet, anastomotic leakage, pulmonary complications, wound dehiscence, length of hospital stay, morbidity, and mortality. Cochrane Collaboration RevMan 5.2 software was used for the meta-analysis. Eight RCT studies fulfilled our inclusion criteria. Of the 1,141 patients in those RCTs, 570 received nasogastric or nasojejunal decompression and 571 did not. Anastomotic leakage, pulmonary complications, wound dehiscence, morbidity, and mortality were comparable between the groups. Stratified by the type of gastrectomy or gastrojejunostomy, no significant differences in above mentioned outcomes were observed in subgroup analyses. The no ND group displayed a significantly shorter time to oral diet (weighted mean difference [WMD]?=?0.45, 95 % confidence interval [CI]?=?0.29 to 0.61, p?
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Biatrial ablation versus limited right atrial ablation for atrial fibrillation associated with atrial septal defect in adults.
Surg. Today
PUBLISHED: 08-09-2014
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To compare the efficacy and safety of limited right atrial ablation versus biatrial ablation for atrial fibrillation (AF) associated with atrial septal defect (ASD) in adults.
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Sample size calculations for prevalent cohort designs.
Stat Methods Med Res
PUBLISHED: 08-06-2014
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Cross-sectional prevalent cohort design has drawn considerable interests in the studies of association between risk factors and time-to-event outcome. The sampling scheme in such design gives rise to length-biased data that require specialized analysis strategy but can improve study efficiency. The power and sample size calculation methods are however lacking for studies with prevalent cohort design, and using the formula developed for traditional survival data may overestimate sample size. We derive the sample size formulas that are appropriate for the design of cross-sectional prevalent cohort studies, under the assumptions of exponentially distributed event time and uniform follow-up for cross-sectional prevalent cohort design. We perform numerical and simulation studies to compare the sample size requirements for achieving the same power between prevalent cohort and incident cohort designs. We also use a large prospective prevalent cohort study to demonstrate the procedure. Using rigorous designs and proper analysis tools, the prospective prevalent cohort design can be more efficient than the incident cohort design with the same total sample sizes and study durations.
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Suprapubic single incision laparoscopic appendectomy.
J. Surg. Res.
PUBLISHED: 08-04-2014
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The single incision method through the umbilicus is commonly used for laparoscopic appendectomy. To obtain a better cosmetic outcome and less surgical complexity, we have designed a new single-incision laparoscopic appendectomy technique performed above the pubic symphysis.
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Femtosecond pulse erbium-doped fiber laser by a few-layer MoS(2) saturable absorber.
Opt Lett
PUBLISHED: 08-01-2014
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We report on the generation of a femtosecond pulse in a fiber ring laser by using a polyvinyl alcohol (PVA)-based molybdenum disulfide (MoS(2)) saturable absorber (SA). With a saturable optical intensity of 34??MW/cm(2) and a modulation depth of ?4.3%, the PVA-based MoS(2) SA had been employed with an erbium-doped fiber ring laser as a mode locker. The mode-locking operation could be achieved at a low pump threshold of 22 mW. A ?710??fs pulse centered at 1569.5 nm wavelength with a repetition rate of 12.09 MHz had been achieved with proper cavity dispersion. With the variation of net cavity dispersion, output pulses with durations from 0.71 to 1.46 ps were obtained. The achievement of a femtosecond pulse at 1.55 ?m waveband demonstrates the broadband saturable absorption of MoS(2), and also indicates that the filmy PVA-based MoS(2) SA is indeed a good candidate for an ultrafast saturable absorption device.
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Systematic comparison of sets of (13)C NMR spectra that are potentially identical. Confirmation of the configuration of a cuticular hydrocarbon from the cane beetle Antitrogus parvulus.
J. Org. Chem.
PUBLISHED: 07-28-2014
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A systematic process is introduced to compare (13)C NMR spectra of two (or more) candidate samples of known structure to a natural product sample of unknown structure. The process is designed for the case where the spectra involved can reasonably be expected to be very similar, perhaps even identical. It is first validated by using published (13)C NMR data sets for the natural product 4,6,8,10,16,18-hexamethyldocosane. Then the stereoselective total syntheses of two candidate isomers of the related 4,6,8,10,16-pentamethyldocosane natural product are described, and the process is applied to confidently assign the configuration of the natural product as (4S,6R,8R,10S,16S). This is accomplished even though the chemical shift differences between this isomer and its (16R)-epimer are only ±5-10 ppb (±0.005-0.01 ppm).
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Hemodynamic performance of the Fontan circulation compared with a normal biventricular circulation: a computational model study.
Am. J. Physiol. Heart Circ. Physiol.
PUBLISHED: 07-25-2014
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The physiological limitations of the Fontan circulation have been extensively addressed in the literature. Many studies emphasized the importance of pulmonary vascular resistance in determining cardiac output (CO) but gave little attention to other cardiovascular properties that may play considerable roles as well. The present study was aimed to systemically investigate the effects of various cardiovascular properties on clinically relevant hemodynamic variables (e.g., CO and central venous pressure). To this aim, a computational modeling method was employed. The constructed models provided a useful tool for quantifying the hemodynamic effects of any cardiovascular property of interest by varying the corresponding model parameters in model-based simulations. Herein, the Fontan circulation was studied compared with a normal biventricular circulation so as to highlight the unique characteristics of the Fontan circulation. Based on a series of numerical experiments, it was found that 1) pulmonary vascular resistance, ventricular diastolic function, and systemic vascular compliance play a major role, while heart rate, ventricular contractility, and systemic vascular resistance play a secondary role in the regulation of CO in the Fontan circulation; 2) CO is nonlinearly related to any single cardiovascular property, with their relationship being simultaneously influenced by other cardiovascular properties; and 3) the stability of central venous pressure is significantly reduced in the Fontan circulation. The findings suggest that the hemodynamic performance of the Fontan circulation is codetermined by various cardiovascular properties and hence a full understanding of patient-specific cardiovascular conditions is necessary to optimize the treatment of Fontan patients.
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[Effect of low-molecular-weight heparin combined with doxorubicin on hepatocellular cancer cell migration in vitro].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 07-25-2014
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To investigate the anti-cancer effect of low-molecular-weight heparin (LMWH) combined with doxorubicin and explore the mechanism.
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Armed oncolytic virus enhances immune functions of chimeric antigen receptor-modified T cells in solid tumors.
Cancer Res.
PUBLISHED: 07-24-2014
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The clinical efficacy of chimeric antigen receptor (CAR)-redirected T cells remains marginal in solid tumors compared with leukemias. Failures have been attributed to insufficient T-cell migration and to the highly immunosuppressive milieu of solid tumors. To overcome these obstacles, we have combined CAR-T cells with an oncolytic virus armed with the chemokine RANTES and the cytokine IL15, reasoning that the modified oncolytic virus will both have a direct lytic effect on infected malignant cells and facilitate migration and survival of CAR-T cells. Using neuroblastoma as a tumor model, we found that the adenovirus Ad5?24 exerted a potent, dose-dependent, cytotoxic effect on tumor cells, whereas CAR-T cells specific for the tumor antigen GD2 (GD2.CAR-T cells) were not damaged. When used in combination, Ad5?24 directly accelerated the caspase pathways in tumor cells exposed to CAR-T cells, whereas the intratumoral release of both RANTES and IL15 attracted CAR-T cells and promoted their local survival, respectively, increasing the overall survival of tumor-bearing mice. These preclinical data support the use of this innovative biologic platform of immunotherapy for solid tumors. Cancer Res; 74(18); 5195-205. ©2014 AACR.
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Invariant NKT cells with chimeric antigen receptor provide a novel platform for safe and effective cancer immunotherapy.
Blood
PUBLISHED: 07-21-2014
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Advances in the design of chimeric antigen receptors (CARs) have improved the antitumor efficacy of redirected T cells. However, functional heterogeneity of CAR T cells limits their therapeutic potential and is associated with toxicity. We proposed that CAR expression in V?24-invariant natural killer T (NKT) cells can build on the natural antitumor properties of these cells while their restriction by monomorphic CD1d limits toxicity. Primary human NKT cells were engineered to express a CAR against the GD2 ganglioside (CAR.GD2), which is highly expressed by neuroblastoma (NB). We compared CAR.GD2 constructs that encoded the CD3? chain alone, with CD28, 4-1BB, or CD28 and 4-1BB costimulatory endodomains. CAR.GD2 expression rendered NKT cells highly cytotoxic against NB cells without affecting their CD1d-dependent reactivity. We observed a striking T helper 1-like polarization of NKT cells by 4-1BB-containing CARs. Importantly, expression of both CD28 and 4-1BB endodomains in the CAR.GD2 enhanced in vivo persistence of NKT cells. These CAR.GD2 NKT cells effectively localized to the tumor site had potent antitumor activity, and repeat injections significantly improved the long-term survival of mice with metastatic NB. Unlike T cells, CAR.GD2 NKT cells did not induce graft-versus-host disease. These results establish the potential of NKT cells to serve as a safe and effective platform for CAR-directed cancer immunotherapy.
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Two-dimensional nanocrystals of molecular Janus particles.
J. Am. Chem. Soc.
PUBLISHED: 07-16-2014
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This paper describes a rational strategy to obtain self-assembled two-dimensional (2D) nanocrystals with definite and uniform thickness from a series of molecular Janus particles based on molecular nanoparticles (MNPs). MNPs are 3D framework with rigid shapes. Three different types of MNPs based on derivatives of polyhedral oligomeric silsesquioxane (POSS), [60]fullerene (C60), and Lindqvist-type polyoxometalate (POM) are used as building blocks to construct these amphiphilic molecular Janus particles by covalently connecting hydrophobic crystalline BPOSS with a charged hydrophilic MNP. The formation of 2D nanocrystals with an exact thickness of double layers of molecules is driven by directional crystallization of the BPOSS MNP and controlled by various factors such as solvent polarity, number of counterions, and sizes of the MNPs. Strong solvating interactions of the ionic MNPs in polar solvents (e.g., acetonitrile and dimethylformamide) are crucial to provide repulsive interactions between the charged outlying ionic MNPs and suppress further aggregation along the layer normal direction. The number of counterions per molecule plays a major role in determining the self-assembled morphologies. Size matching of the hydrophobic and ionic MNPs is another critical factor in the formation of 2D nanocrystals. Self-assembly of rationally designed molecular Janus particles provides a unique "bottom-up" strategy to engineer 2D nanostructures.
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Inhibition of TNF-? in hypothalamic paraventricular nucleus attenuates hypertension and cardiac hypertrophy by inhibiting neurohormonal excitation in spontaneously hypertensive rats.
Toxicol. Appl. Pharmacol.
PUBLISHED: 07-12-2014
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We hypothesized that chronic inhibition of tumor necrosis factor-alpha (TNF-?) in the hypothalamic paraventricular nucleus (PVN) delays the progression of hypertension and attenuates cardiac hypertrophy by up-regulating anti-inflammatory cytokines, reducing pro-inflammatory cytokines (PICs), decreasing nuclear factor-?B (NF-?B) p65 and NAD(P)H oxidase activities, as well as restoring the neurotransmitters balance in the PVN of spontaneously hypertensive rats (SHR). Adult normotensive Wistar-Kyoto (WKY) and SHR rats received bilateral PVN infusion of a TNF-? blocker (pentoxifylline or etanercept) or vehicle for 4weeks. SHR rats showed higher mean arterial pressure and cardiac hypertrophy compared with WKY rats, as indicated by increased whole heart weight/body weight ratio, whole heart weight/tibia length ratio, left ventricular weight/tibia length ratio, and cardiac atrial natriuretic peptide (ANP) and beta-myosin heavy chain (?-MHC) mRNA expressions. Compared with WKY rats, SHR rats had higher PVN levels of tyrosine hydroxylase, PICs, the chemokine monocyte chemoattractant protein-1 (MCP-1), NF-?B p65 activity, mRNA expressions of NOX-2 and NOX-4, and lower PVN levels of IL-10 and 67-kDa isoform of glutamate decarboxylase (GAD67), and higher plasma norepinephrine. PVN infusion of pentoxifylline or etanercept attenuated all these changes in SHR rats. These findings suggest that SHR rats have an imbalance between excitatory and inhibitory neurotransmitters, as well as an imbalance between pro- and anti-inflammatory cytokines in the PVN; and chronic inhibition of TNF-? in the PVN delays the progression of hypertension by restoring the balances of neurotransmitters and cytokines in the PVN, and attenuating PVN NF-?B p65 activity and oxidative stress, thereby attenuating hypertension-induced sympathetic hyperactivity and cardiac hypertrophy.
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Comparison of diffusion-weighted MRI acquisition techniques for normal pancreas at 3.0 Tesla.
Diagn Interv Radiol
PUBLISHED: 07-11-2014
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We aimed to optimize diffusion-weighted imaging (DWI) acquisitions for normal pancreas at 3.0 Tesla.
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Pri-miR-34b/c rs4938723 TC heterozygote is associated with increased cancer risks: evidence from published data.
Tumour Biol.
PUBLISHED: 07-09-2014
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The promoter region of the microRNA pri-miR-34b/c has a potentially functional polymorphism, rs4938723, located in a typical CpG island. Studies of the association between pri-miR-34b/c rs4938723 polymorphism and risks of various cancers have had inconsistent results. We therefore conducted a meta-analysis of nine studies that included 6,036 cancer patients and 7,490 controls to address this association. Overall, this meta-analysis showed the pri-miR-34b/c rs4938723 TC heterozygote to be significantly associated with increased risk of overall cancers compared with the wild-type TT genotype (P?=?0.010, odds ratio (OR)?=?1.10, 95 % confidence interval (CI) 1.02-1.18). In stratified analysis, the TC heterozygote was significantly associated with increased cancers risks in digestive tract cancers, in hepatocellular cancer, in Asian population and in the large-sample subgroup. The CC genotypes of rs4938723 were also associated with increased hepatocellular cancer risk but associated with decreased colorectal cancer risk in the stratification analysis by a single cancer type. Thus our meta-analysis suggests that the pri-miR-34b/c rs4938723 TC heterozygote contributes to increased overall cancer risks, as well as shown in digestive tract cancers, in hepatocellular cancer, in Asian population and in the large-sample subgroup. This rs4938723 SNP showed an opposite tendency orientation between the hepatocellular cancer and colorectal cancer risks. Large-sample studies are needed to verify our findings.
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Endoplasmic Reticulum Stress, Diabetes Mellitus, and Tissue Injury.
Curr. Protein Pept. Sci.
PUBLISHED: 07-03-2014
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Endoplasmic reticulum (ER) stress is characterized by the accumulation of unfolded and misfolded proteins in the ER lumen. Unfolded and misfolded protein accumulation interferes with the ER function and triggers ER stress response. Thus, ER stress response, also called unfolded protein response (UPR), is an adaptive process that controls the protein amount in the ER lumen and the downstream protein demand. In normal conditions, the role of ER stress is to maintain ER homeostasis, restore ER function, and protect stressed cells from apoptosis, by coordinating gene expression, protein synthesis, and accelerating protein degradation through several molecular pathways. However, prolonged ER stress response plays a paradoxical role, which leads to cell damage, apoptosis, and concomitant tissue injuries. A number of tissue alterations are involved with diabetes mellitus progress and its comorbidities via ER stress. However, certain pharmacological agents affecting ER stress have been identified. In this review, we summarized the relationship between ER stress and insulin resistance development. Moreover, we aim to explain how ER stress influences type 2 diabetes mellitus (T2DM) development. In addition, we reviewed the literature on ER stress and UPR in three kinds of tissue injuries induced by T2DM. Finally, a retrospective analysis of the effects of anti-diabetes medications on ER stress is presented.
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Biohydrogen facilitated denitrification at biocathode in bioelectrochemical system (BES).
Bioresour. Technol.
PUBLISHED: 07-03-2014
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Reductive removal of nitrate in bioelectrochemical system (BES) at abiotic cathode, biocathode and biohydrogen facilitated biocathode were investigated. It was found that nitrate removal efficiency reached 95% and 59% at the biohydrogen facilitated biocathode and biocathode respectively, while which was only 13% at the abiotic cathode. Meanwhile, activity of nitrate reductase reached 0.701 g-N/Lh for the biohydrogen facilitated group, which was about 9.3 times of the biocathode group. Moreover, electrochemical performances as power density, ohmic resistance, and polarization resistance of the biohydrogen facilitated group reached 76.96 mW/m(3), 8.63 ohm and 383 ohm, respectively, which were better than two other groups. Finally, an obvious shift of bacterial community responsible for the enhanced nitrate reduction between the two biocathode groups was observed. Therefore, nitrate reduction in BES could be enhanced at the biocathode than that of the abiotic cathode, and then be further boosted with the combination of biohydrogen.
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[Study on foraging behaviors of honeybee Apis mellifera based on RFID technology].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 07-03-2014
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Honeybee foragers can flexibly adjust their out-hive activities to ensure growth and reproduction of the colony. In order to explore the characteristics of honey bees foraging behaviors, in this study, their flight activities were monitored 24 hours per day for a duration of 38 days, using an radio frequency identification (RFID) system designed and manufactured by the Honeybee Research Institute of Jiangxi Agricultural University in cooperation with the Guangzhou Invengo Information Technology Co., Ltd. Our results indicated that 63.4% and 64.5% of foragers were found rotating more than one day off during the foraging period in two colonies, and 22.5% and 26.4% of the total foraging days were used for rest respectively. Further, although the total foraging time between rotating day-off foragers and continuously working foragers was equal, the former had a significant longer lifespan than the latter. Additionally, the lifespan of the early developed foragers was significantly lower than that of the normally developed foragers. This study enriched the content of foraging behaviors of honey bees, and it could be used as the basis for the further explorations on evolutionary mechanism of foraging behaviors of eusocial insects.
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Optimal treatment determination on the basis of haematoma volume and intra-cerebral haemorrhage score in patients with hypertensive putaminal haemorrhages: a retrospective analysis of 310 patients.
BMC Neurol
PUBLISHED: 06-30-2014
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Hypertensive putaminal haemorrhage comprises major part of intra-cerebral haemorrhages, with particularly high morbidity and mortality. However, the optimal treatments for these individuals remain controversial.
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Batteries. Capturing metastable structures during high-rate cycling of LiFePO? nanoparticle electrodes.
Science
PUBLISHED: 06-28-2014
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The absence of a phase transformation involving substantial structural rearrangements and large volume changes is generally considered to be a key characteristic underpinning the high-rate capability of any battery electrode material. In apparent contradiction, nanoparticulate LiFePO4, a commercially important cathode material, displays exceptionally high rates, whereas its lithium-composition phase diagram indicates that it should react via a kinetically limited, two-phase nucleation and growth process. Knowledge concerning the equilibrium phases is therefore insufficient, and direct investigation of the dynamic process is required. Using time-resolved in situ x-ray powder diffraction, we reveal the existence of a continuous metastable solid solution phase during rapid lithium extraction and insertion. This nonequilibrium facile phase transformation route provides a mechanism for realizing high-rate capability of electrode materials that operate via two-phase reactions.
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Activity of broad-spectrum T cells as treatment for AdV, EBV, CMV, BKV, and HHV6 infections after HSCT.
Sci Transl Med
PUBLISHED: 06-27-2014
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It remains difficult to treat the multiplicity of distinct viral infections that afflict immunocompromised patients. Adoptive transfer of virus-specific T cells (VSTs) can be safe and effective, but such cells have been complex to prepare and limited in antiviral range. We now demonstrate the feasibility and clinical utility of rapidly generated single-culture VSTs that recognize 12 immunogenic antigens from five viruses (Epstein-Barr virus, adenovirus, cytomegalovirus, BK virus, and human herpesvirus 6) that frequently cause disease in immunocompromised patients. When administered to 11 recipients of allogeneic transplants, 8 of whom had up to four active infections with the targeted viruses, these VSTs proved safe in all subjects and produced an overall 94% virological and clinical response rate that was sustained long-term.
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Comparison of one versus two cages in lumbar interbody fusion for degenerative lumbar spinal disease: a meta-analysis.
Orthop Surg
PUBLISHED: 05-27-2014
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To systematically compare the fusion rate and safety of lumbar interbody fusion using one cage versus two cages for the treatment of degenerative lumbar spinal diseases.
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Connecting endoplasmic reticulum stress to autophagy through IRE1/JNK/beclin-1 in breast cancer cells.
Int. J. Mol. Med.
PUBLISHED: 05-27-2014
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Current experimental results indicate that endoplasmic reticulum (ER) stress activates the unfolded protein response (UPR), which rebuilds ER homeostasis, through which tumor cells can become resistant chemotherapeutic agents. Autophagy is a form of programmed cell death, but it can also play a cytoprotective role in tumor cells, indicating that it has an inverse function. The aim of the present study was to investigate whether tunicamycin (TM) induces autophagy, as well as whether the inhibition of autophagy enhances the apoptosis ofbreast cancer cells induced by TM. In addition, we wished to investigate the mechanisms through which specific UPR targets control autophagy. We found that MCF-7 and MDA-MB?231 breast cancer cells were insensitive to TM at a relatively low concentration. As shown by western blot analysis, treatment with TM increased the expression of 78 kDa glucose-regulated protein (GRP78), inositol requiring enzyme 1 (IRE1), beclin-1, IRE1?, p-JNK and microtubule-associated protein 1 light chain 3 (LC3); the expression of p62 increased at an early time point during treatment and subsequently decreased. We also used the specific inhibitor of autophagy, 3-methyladenine (3-MA), to elucidate the role of autophagy in ER stress in the breast cancer cells treated with TM. The transformation of LC3-I to LC3-II which was induced by TM, was reversed following treatment with 3-MA. The inhibition of autophagy by 3-MA treatment enhanced the inhibitory and apoptotic rates of TM in the breast cancer cells, as shown by confocal microscopy and flow cytometry. TM increased the misfolded proteins that lead to the activation of ER stress-mediated protection and induced apoptosis paralleled by autophagy in breast cancer cells which was regulated by IRE1/JNK/beclin-1. Autophagy attenuates ER stress by clearing ubiquitinated proteins and decreasing apoptosis, which plays a protective role. The inhibition of autophagy or the promotion of ER stress may be used as therapeutic targets to improve the efficacy of chemotherapeutic drugs.
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AKT/GSK-3? regulates stability and transcription of snail which is crucial for bFGF-induced epithelial-mesenchymal transition of prostate cancer cells.
Biochim. Biophys. Acta
PUBLISHED: 05-15-2014
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Epithelial-mesenchymal transition (EMT) plays a pivotal role in the development of metastatic cancers. Basic fibroblast growth factor (bFGF) is significantly elevated in metastatic prostate cancers, which has been mentioned mainly to induce EMT in normal cells. However, there is no description about bFGF induced EMT and its underlying mechanism in prostate cancer cells.
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Preparation and in vivo efficient anti-infection property of GTR/GBR implant made by metronidazole loaded electrospun polycaprolactone nanofiber membrane.
Int J Pharm
PUBLISHED: 04-29-2014
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Infection is the major reason of GTR/GBR membrane failure in clinical application. In this work, we developed GTR/GBR nanofiber membranes with localized drug delivery function to prevent infection. Metronidazole (MNA), an antibiotic, was successfully incorporated into electrospun polycaprolactone (PCL) nanofibers at different concentrations (0, 1, 5, 10, 20, 30, and 40wt% polymer). To obtain the optimum anti-infection membrane, we systematically investigated the physical-chemical and mechanical properties of the nanofiber membranes with different drug contents. The interaction between PCL and MNA was identified by molecular dynamics simulation. MNA released in a controlled, sustained manner over 2 weeks and the antibacterial activity of the released MNA remained. The incorporation of MNA improved the hydrophilicity and in vitro biodegradation rate of PCL nanofibers. The nanofiber membranes allowed cells to adhere to and proliferate on them and showed excellent barrier function. The membrane loaded with 30% MNA had the best comprehensive properties. Analysis of subcutaneous implants demonstrated that MNA-loaded nanofibers evoked a less severe inflammatory response than pure PCL nanofibers. These results demonstrate the potential of MNA-loaded nanofiber membranes as GTR/GBR membrane with antibacterial and anti-inflammatory function for extensive biomedical applications.
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Hexokinase II inhibitor, 3-BrPA induced autophagy by stimulating ROS formation in human breast cancer cells.
Genes Cancer
PUBLISHED: 04-22-2014
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Hexokinase II (HKII), a key enzyme of glycolysis, is widely over-expressed in cancer cells. 3-bromopyruvate (3-BrPA), an inhibitor of HK II, has been proposed as a specific antitumor agent. Autophagy is a process that regulates the balance between protein synthesis and protein degradation. Autophagy in mammalian systems occurs under basal conditions and can be stimulated by stresses, including starvation, oxidative stress. Therefore, we hypothesized that 3-BrPA could induce autophagy. In the present study, we explored the mechanism of 3-BrPA and its combined action with chloroquine. Our results demonstrate that in MDA-MB-435 and in MDA-MB-231 cells, 3-BrPA induces autophagy, which can be inhibited by chloroquine. Furthermore, the combined treatment synergistically decreased the number of viable cells. Interestingly, the combined treatment triggered apoptosis in MDA-MB-435 cells, while it induced necroptosis in MDA-MB-231 cells. ROS mediated cell death when 3-BrPA and CQ were co-administered. Finally, CQ enhanced the anticancer efficacy of 3-BrPA in vivo. Collectively, our results show that 3-BrPA triggers autophagy, increasing breast cancer cell resistance to 3-BrPA treatment and that CQ enhanced 3-BrPA-induced cell death in breast cancer cells by stimulating ROS formation. Thus, inhibition of autophagy may be an innovative strategy for adjuvant chemotherapy of breast cancer.human skeletal muscle. Efficient Mirk depletion in SU86.86 pancreatic cancer cells by an inducible shRNA decreased expression of eight antioxidant genes. Thus both cancer cells and differentiated myotubes utilize Mirk kinase to relieve oxidative stress.
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Central prolactin receptors (PRLRs) regulate hepatic insulin sensitivity in mice via signal transducer and activator of transcription 5 (STAT5) and the vagus nerve.
Diabetologia
PUBLISHED: 04-04-2014
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Recent studies have revealed the crucial role of the central nervous system (CNS), especially the hypothalamus, in the regulation of insulin sensitivity in peripheral tissues. The aim of our current study was to investigate the possible involvement of hypothalamic prolactin receptors (PRLRs) in the regulation of hepatic insulin sensitivity.
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Inflammatory myofibroblastic tumor of the thigh without bone involvement: a case report.
World J Surg Oncol
PUBLISHED: 03-30-2014
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Inflammatory myofibroblastic tumors are rare, and those located in the extremities without bone involvement are even rarer. We present the case of a 61-year-old Chinese male patient with an inflammatory myofibroblastic tumor of the right thigh. It was excised and a histopathologic examination revealed an inflammatory myofibroblastic tumor. This case is presented by virtue of its rare location.
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Isolation and complete nucleotide sequence of a Batai virus strain in Inner Mongolia, China.
Virol. J.
PUBLISHED: 03-27-2014
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Batai virus (BATV) is a member of the Orthobunyavirus genus of the family Bunyaviridae, and a vector-borne pathogen. Genomic variations of BATV exist in different regions of the world, due to genetic reassortment. Whole-genome sequencing of any isolate is necessary for a phylogenetic analysis. In 1998, a BATV strain was isolated from an Anopheles philippines mosquito in Yunnan Province, China. This strain has not been found to infect any other host. We investigated BATV infection in cattle in Inner Mongolia, China and performed deep sequencing of the genome of the BATV isolate.
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Treatment of osteoblastoma at C3-4 in a child: a case report.
BMC Musculoskelet Disord
PUBLISHED: 03-23-2014
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Osteoblastoma is a rare and benign osteoid-producing primary bone tumor that affects mainly the long bones. 36% of these tumors are observed around the spine and the vast majority arises around the posterior.
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Techniques and feasibility of laparoscopic extended right hemicolectomy with D3 lymphadenectomy.
World J. Gastroenterol.
PUBLISHED: 03-23-2014
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To illustrate the critical techniques and feasibility of laparoscopic extended right hemicolectomy (LERH), according to our previous experience.
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Self-assembly of fullerene-based janus particles in solution: effects of molecular architecture and solvent.
Chemistry
PUBLISHED: 03-20-2014
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Two molecular Janus particles based on amphiphilic [60]fullerene (C60 ) derivatives were designed and synthesized by using the regioselective Bingel-Hirsh reaction and the click reaction. These particles contain carboxylic acid functional groups, a hydrophilic fullerene (AC60 ), and a hydrophobic C60 in different ratios and have distinct molecular architectures: 1:1 (AC60 -C60 ) and 1:2 (AC60 -2C60 ). These molecular Janus particles can self-assemble in solution to form aggregates with various types of micellar morphology. Whereas vesicular morphology was observed for both AC60 -C60 and AC60 -2C60 in tetrahydrofuran, in a mixture of N,N-dimethylformamide (DMF)/water, spherical micelles and cylindrical micelles were observed for AC60 -C60 and AC60 -2C60 , respectively. A mechanism of formation was tentatively proposed based on the effects of molecular architecture and solvent polarity on self-assembly.
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Needle morphological evidence of the homoploid hybrid origin of Pinus densata based on analysis of artificial hybrids and the putative parents, Pinus tabuliformis and Pinus yunnanensis.
Ecol Evol
PUBLISHED: 03-11-2014
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Genetic analyses indicate that Pinus densata is a natural homoploid hybrid originating from Pinus tabuliformis and Pinus yunnanensis. Needle morphological and anatomical features show relative species stability and can be used to identify coniferous species. Comparative analyses of these needle characteristics and phenotypic differences between the artificial hybrids, P. densata, and parental species can be used to determine the genetic and phenotypic evolutionary consequences of natural hybridization. Twelve artificial hybrid families, the two parental species, and P. densata were seeded in a high-altitude habitat in Linzhi, Tibet. The needles of artificial hybrids and the three pine species were collected, and 24 needle morphological and anatomical traits were analyzed. Based on these results, variations in 10 needle traits among artificial hybrid families and 22 traits among species and artificial hybrids were predicted and found to be under moderate genetic control. Nineteen needle traits in artificial hybrids were similar to those in P. densata and between the two parental species, P. tabuliformis and P. yunnanensis. The ratio of plants with three needle clusters in artificial hybrids was 22.92%, which was very similar to P. densata. The eight needle traits (needle length, the mean number of stomata in sections 2 mm in length of the convex and flat sides of the needle, mean stomatal density, mesophyll/vascular bundle area ratio, mesophyll/resin canal area ratio, mesophyll/(resin canals and vascular bundles) area ratio, vascular bundle/resin canal area ratio) relative to physiological adaptability were similar to the artificial hybrids and P. densata. The similar needle features between the artificial hybrids and P. densata could be used to verify the homoploid hybrid origin of P. densata and helps to better understand of the hybridization roles in adaptation and speciation in plants.
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Microbiologically induced deterioration of concrete--a review.
Braz. J. Microbiol.
PUBLISHED: 03-10-2014
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Microbiologically induced deterioration (MID) causes corrosion of concrete by producing acids (including organic and inorganic acids) that degrade concrete components and thus compromise the integrity of sewer pipelines and other structures, creating significant problems worldwide. Understanding of the fundamental corrosion process and the causal agents will help us develop an appropriate strategy to minimize the costs in repairs. This review presents how microorganisms induce the deterioration of concrete, including the organisms involved and their colonization and succession on concrete, the microbial deterioration mechanism, the approaches of studying MID and safeguards against concrete biodeterioration. In addition, the uninvestigated research area of MID is also proposed.
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Laparoscopic vs open extended right hemicolectomy for colon cancer.
World J. Gastroenterol.
PUBLISHED: 01-22-2014
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To evaluate the feasibility, safety, and oncologic outcomes of laparoscopic extended right hemicolectomy (LERH) for colon cancer.
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Synthesis and biological evaluation of 4-(1,2,3-triazol-1-yl)coumarin derivatives as potential antitumor agents.
Bioorg. Med. Chem. Lett.
PUBLISHED: 01-15-2014
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In this research, a series of 4-(1,2,3-triazol-1-yl)coumarin conjugates were synthesized and their anticancer activities were evaluated in vitro against three human cancer cell lines, including human breast carcinoma MCF-7 cell, colon carcinoma SW480 cell and lung carcinoma A549 cell. To increase the biological potency, structural optimization campaign was conducted focusing on the C-4 position of 1,2,3-triazole and the C-6, C-7 positions of coumarin. In addition, to further evaluate the role of 1,2,3-triazole and coumarin for antiproliferative activity, 9 compounds possessing 4-(piperazin-1-yl)coumarin framework and 3 derivatives baring quinoline core were also synthesized. By MTT assay in vitro, most of the compounds display attractive antitumor activities, especially 23. Further flow cytometry assays demonstrate that compound 23 exerts the antiproliferative role through arresting G2/M cell-cycle and inducing apoptosis.
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Is early oral feeding after gastric cancer surgery feasible? A systematic review and meta-analysis of randomized controlled trials.
PLoS ONE
PUBLISHED: 01-01-2014
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To assess the feasibility and safety of early oral feeding (EOF) after gastrectomy for gastric cancer through a systematic review and meta-analysis based on randomized controlled trials.
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Similarity from multi-dimensional scaling: solving the accuracy and diversity dilemma in information filtering.
PLoS ONE
PUBLISHED: 01-01-2014
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Recommender systems are designed to assist individual users to navigate through the rapidly growing amount of information. One of the most successful recommendation techniques is the collaborative filtering, which has been extensively investigated and has already found wide applications in e-commerce. One of challenges in this algorithm is how to accurately quantify the similarities of user pairs and item pairs. In this paper, we employ the multidimensional scaling (MDS) method to measure the similarities between nodes in user-item bipartite networks. The MDS method can extract the essential similarity information from the networks by smoothing out noise, which provides a graphical display of the structure of the networks. With the similarity measured from MDS, we find that the item-based collaborative filtering algorithm can outperform the diffusion-based recommendation algorithms. Moreover, we show that this method tends to recommend unpopular items and increase the global diversification of the networks in long term.
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Divergent Gene Activation in Peripheral Blood and Tissues of Patients with Rheumatoid Arthritis, Psoriatic Arthritis and Psoriasis following Infliximab Therapy.
PLoS ONE
PUBLISHED: 01-01-2014
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The immune inflammatory disorders rheumatoid arthritis (RA), psoriatic arthritis (PsA) and psoriasis (Ps) share common pathologic features and show responsiveness to anti-tumor necrosis factor (TNF) agents yet they are phenotypically distinct. The aim of this study was to examine if anti-TNF therapy is associated with divergent gene expression profiles in circulating cells and target tissues of patients with these diseases.
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Molecular imaging of integrin ?v?6 expression in living subjects.
Am J Nucl Med Mol Imaging
PUBLISHED: 01-01-2014
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Integrins, a family of cell adhesion molecules composed of ? and ? heterodimeric subunits, are involved in a wide range of cell-extracellular matrix and cell-cell interactions. The study of integrin family members as targets for molecular imaging and therapy has been generally limited with the exception of integrin ?v?3. v?6, a member of the integrin family, is expressed at low or undetectable levels in normal tissues, but is widely upregulated during many pathological and physiological processes, especially cancer and fibrosis, making it a promising target for molecular imaging. Noninvasive and quantitative imaging of integrin v?6 expression would be very useful for disease diagnosis, treatment monitoring, and prognosis assessment. Although various molecular probes have been developed for positron emission tomography and single-photon emission computed tomography imaging of integrin v?6 expression in preclinical animal models, further research efforts are required to optimize integrin v?6-targeting probes for future potential clinical applications in the fields of oncology and beyond.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.